US5872728A - Process for computing the coefficients of an adaptive filter in an echo-cancellor - Google Patents
Process for computing the coefficients of an adaptive filter in an echo-cancellor Download PDFInfo
- Publication number
- US5872728A US5872728A US08/831,271 US83127197A US5872728A US 5872728 A US5872728 A US 5872728A US 83127197 A US83127197 A US 83127197A US 5872728 A US5872728 A US 5872728A
- Authority
- US
- United States
- Prior art keywords
- computing
- estimation
- accordance
- formula
- echo
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/02—Details
- H04B3/20—Reducing echo effects or singing; Opening or closing transmitting path; Conditioning for transmission in one direction or the other
- H04B3/23—Reducing echo effects or singing; Opening or closing transmitting path; Conditioning for transmission in one direction or the other using a replica of transmitted signal in the time domain, e.g. echo cancellers
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H21/00—Adaptive networks
- H03H21/0012—Digital adaptive filters
- H03H2021/007—Computation saving measures; Accelerating measures
- H03H2021/0076—Measures relating to the convergence time
- H03H2021/0078—Measures relating to the convergence time varying the step size
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Filters That Use Time-Delay Elements (AREA)
- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Abstract
Description
e=y-y
Σ.sub.s (n+1)=(1-μ)Σ.sub.s (n)+μx.sup.2 (n)
Σ.sub.1 (n+1)=(1-γ)Σ.sub.1 (n)+γx.sup.2 (n)
C.sub.i (n+1)=C.sub.i (n)-αe (n+1)x(n+i+1)
e=y-y
Σ.sub.s (n+1)=(1-μ)Σ.sub.s (n)+μx.sup.2 (n)
Σ.sub.1 (n+1)=(1-γ)Σ.sub.1 (n)+γx.sup.2 (n)
C.sub.i (n+1)=C.sub.i (n)-αe (n+)x(n+1=1)
Claims (5)
e=y-y
Σ.sub.s (n+1)=(1-μ)Σ.sub.s (n)+μx.sup.2 (n)
Σ.sub.1 (n+1)=(1-γ)Σ.sub.1 (n)+γx.sup.2 (n)
C.sub.1 (n+1)=C.sub.i (n)-αe(n+1)x(n+i+1).
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP96480085 | 1996-06-20 | ||
EP96480085 | 1996-06-20 |
Publications (1)
Publication Number | Publication Date |
---|---|
US5872728A true US5872728A (en) | 1999-02-16 |
Family
ID=8225446
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US08/831,271 Expired - Lifetime US5872728A (en) | 1996-06-20 | 1997-03-31 | Process for computing the coefficients of an adaptive filter in an echo-cancellor |
Country Status (1)
Country | Link |
---|---|
US (1) | US5872728A (en) |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2348092A (en) * | 1999-01-12 | 2000-09-20 | Motorola Inc | Adaptive step size for filter for echo cancellation |
GB2356328A (en) * | 1999-11-11 | 2001-05-16 | Motorola Israel Ltd | Echo cancellation |
US6850783B1 (en) * | 1998-08-07 | 2005-02-01 | Ericsson Inc. | Methods and apparatus for mitigating the effects of microphone overload in echo cancelation systems |
US20060119969A1 (en) * | 2004-12-03 | 2006-06-08 | Hutchins Robert A | Dynamically adapting a magnetic tape read channel equalizer |
US20100124337A1 (en) * | 2008-11-20 | 2010-05-20 | Harman International Industries, Incorporated | Quiet zone control system |
US20100124336A1 (en) * | 2008-11-20 | 2010-05-20 | Harman International Industries, Incorporated | System for active noise control with audio signal compensation |
US20100177905A1 (en) * | 2009-01-12 | 2010-07-15 | Harman International Industries, Incorporated | System for active noise control with parallel adaptive filter configuration |
US20100260345A1 (en) * | 2009-04-09 | 2010-10-14 | Harman International Industries, Incorporated | System for active noise control based on audio system output |
US20100266134A1 (en) * | 2009-04-17 | 2010-10-21 | Harman International Industries, Incorporated | System for active noise control with an infinite impulse response filter |
US20100290635A1 (en) * | 2009-05-14 | 2010-11-18 | Harman International Industries, Incorporated | System for active noise control with adaptive speaker selection |
US20110019833A1 (en) * | 2008-01-31 | 2011-01-27 | Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E. V. | Apparatus and method for computing filter coefficients for echo suppression |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4789994A (en) * | 1987-08-12 | 1988-12-06 | American Telephone And Telegraph Company, At&T Bell Laboratories | Adaptive equalizer using precursor error signal for convergence control |
US5390364A (en) * | 1992-11-02 | 1995-02-14 | Harris Corporation | Least-mean squares adaptive digital filter havings variable size loop bandwidth |
US5615233A (en) * | 1992-07-22 | 1997-03-25 | Motorola, Inc. | Method for channel estimation using individual adaptation |
-
1997
- 1997-03-31 US US08/831,271 patent/US5872728A/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4789994A (en) * | 1987-08-12 | 1988-12-06 | American Telephone And Telegraph Company, At&T Bell Laboratories | Adaptive equalizer using precursor error signal for convergence control |
US5615233A (en) * | 1992-07-22 | 1997-03-25 | Motorola, Inc. | Method for channel estimation using individual adaptation |
US5390364A (en) * | 1992-11-02 | 1995-02-14 | Harris Corporation | Least-mean squares adaptive digital filter havings variable size loop bandwidth |
Cited By (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6850783B1 (en) * | 1998-08-07 | 2005-02-01 | Ericsson Inc. | Methods and apparatus for mitigating the effects of microphone overload in echo cancelation systems |
GB2348092A (en) * | 1999-01-12 | 2000-09-20 | Motorola Inc | Adaptive step size for filter for echo cancellation |
GB2348092B (en) * | 1999-01-12 | 2001-04-18 | Motorola Inc | Adapative step size for filter and method therefor |
GB2356328A (en) * | 1999-11-11 | 2001-05-16 | Motorola Israel Ltd | Echo cancellation |
GB2356328B (en) * | 1999-11-11 | 2002-10-30 | Motorola Israel Ltd | Echo suppression and echo cancellation |
US20070206310A1 (en) * | 2004-12-03 | 2007-09-06 | Hutchins Robert A | Dynamically adapting a magnetic tape read channel equalizer |
US7271971B2 (en) | 2004-12-03 | 2007-09-18 | International Business Machines Corporation | Dynamically adapting a magnetic tape read channel equalizer |
US7359135B2 (en) | 2004-12-03 | 2008-04-15 | International Business Machines Corporation | Dynamically adapting a magnetic tape read channel equalizer |
US20060119969A1 (en) * | 2004-12-03 | 2006-06-08 | Hutchins Robert A | Dynamically adapting a magnetic tape read channel equalizer |
US20110019833A1 (en) * | 2008-01-31 | 2011-01-27 | Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E. V. | Apparatus and method for computing filter coefficients for echo suppression |
US8462958B2 (en) | 2008-01-31 | 2013-06-11 | Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V. | Apparatus and method for computing filter coefficients for echo suppression |
US8315404B2 (en) | 2008-11-20 | 2012-11-20 | Harman International Industries, Incorporated | System for active noise control with audio signal compensation |
US8270626B2 (en) | 2008-11-20 | 2012-09-18 | Harman International Industries, Incorporated | System for active noise control with audio signal compensation |
US9020158B2 (en) | 2008-11-20 | 2015-04-28 | Harman International Industries, Incorporated | Quiet zone control system |
US20100124336A1 (en) * | 2008-11-20 | 2010-05-20 | Harman International Industries, Incorporated | System for active noise control with audio signal compensation |
US8135140B2 (en) | 2008-11-20 | 2012-03-13 | Harman International Industries, Incorporated | System for active noise control with audio signal compensation |
US20100124337A1 (en) * | 2008-11-20 | 2010-05-20 | Harman International Industries, Incorporated | Quiet zone control system |
US8718289B2 (en) | 2009-01-12 | 2014-05-06 | Harman International Industries, Incorporated | System for active noise control with parallel adaptive filter configuration |
US20100177905A1 (en) * | 2009-01-12 | 2010-07-15 | Harman International Industries, Incorporated | System for active noise control with parallel adaptive filter configuration |
US20100260345A1 (en) * | 2009-04-09 | 2010-10-14 | Harman International Industries, Incorporated | System for active noise control based on audio system output |
US8189799B2 (en) | 2009-04-09 | 2012-05-29 | Harman International Industries, Incorporated | System for active noise control based on audio system output |
US8199924B2 (en) | 2009-04-17 | 2012-06-12 | Harman International Industries, Incorporated | System for active noise control with an infinite impulse response filter |
US20100266134A1 (en) * | 2009-04-17 | 2010-10-21 | Harman International Industries, Incorporated | System for active noise control with an infinite impulse response filter |
US8077873B2 (en) | 2009-05-14 | 2011-12-13 | Harman International Industries, Incorporated | System for active noise control with adaptive speaker selection |
US20100290635A1 (en) * | 2009-05-14 | 2010-11-18 | Harman International Industries, Incorporated | System for active noise control with adaptive speaker selection |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: IBM CORPORATION, NEW YORK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:RICHTER, G.;REEL/FRAME:008626/0371 Effective date: 19970310 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
AS | Assignment |
Owner name: CISCO TECHNOLOGY, INC., A CORPORATION OF CALIFORNI Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:CISCO SYSTEMS, INC., A CORPORATION OF CALIFORNIA;REEL/FRAME:010756/0122 Effective date: 20000405 |
|
AS | Assignment |
Owner name: CISCO SYSTEMS, INC., CALIFORNIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:INTERNATIONAL BUSINESS MACHINES CORPORATION;REEL/FRAME:010832/0878 Effective date: 20000126 |
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Year of fee payment: 4 |
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